I'm at my whits end. I have a 09 Pontiac Vibe GT with 178k. I bought the car about 7 months ago and have done a lot of work to it, motor mounts, axles, tie rods, alternator and much more. One issue is a pretty bad vibration at idle that I can't figure out. We have done normal maintenance like plugs, coils and wires plus removed and cleaned the throttle body in addition to multiple bottles of fuel injector cleaners, Lucas, royal purple and BG but it's not any better and it's not throwing any codes. I been using the car for Uber in Phoenix since losing my job so I try my best to keep it running top notch but can't figure this one out. PLEASE HELP!
When I get a vehicle without service records, I will go through it and change out all wearable stuff like filters, belts, spark plugs and fluids so I have a starting point, It makes it much easier to isolate and solve problems later on.
Check for vacuum leaks at the intake system. How old is your PCV valve?
I'm not sure to be honest. The car came with no service records when I got it. If something seems not right I have just replaced it, usually minor things